The invention relates to a method for current control in a direct voltage network of a direct voltage converter which transmits energy between two direct voltage networks with different direct voltage, and wherein the current control controls a current in one of the direct voltage networks, as well as a direct voltage converter.
A method for operating a DC voltage converter in a hybrid vehicle which has two on-board networks with different voltage is disclosed in DE 10 2007 038 587 A1. The first on-board network is the normal on-board network of the vehicle, which, for cars, usually provides 12 V and is used to supply the control devices and/or auxiliary equipment of the hybrid vehicle. The second on-board network, which is referred to as the high-voltage on-board network, carries a higher voltage level of 230 V, for example, to supply the voltage to the electric motor contained in the hybrid vehicle. The DC voltage converter, which is also referred to as a DC/DC converter, transmits electrical power between the two on-board networks. By means of such a DC voltage converter, energy can be transmitted bidirectionally between the energy storage units which are arranged both in the high-voltage direct voltage network and in the low-voltage direct voltage network.
Hybrid vehicles have been disclosed in which the current of the low-voltage voltage network can be controlled when the direct voltage converter transmits energy from the high-voltage direct voltage network into the low-voltage direct voltage network, which is referred to as so-called buck operation. If, for reasons of configuration of the hybrid drive of the hybrid vehicle, the current in the high-voltage direct voltage network is to be controlled, additional hardware must be created which increases the costs for manufacturing the hybrid drive.